Hide the autocomplete Tableview when text field is empty - objective-c

Question

The following code will generate a custom autocomplete Table View autocompleteTableView below my text field txtActivity. How do I hide the Table View when text field is empty.
- (void)viewDidLoad
{
[super viewDidLoad];
self.txtActivity.delegate = self;
[self cofigureAutoComTableView];
}
- (BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)rangereplacementString:(NSString *)string
{
autocompleteTableView.hidden = NO;
NSString *substring = [NSString stringWithString:textField.text];
substring = [substring stringByReplacingCharactersInRange:range withString:string];
[self searchAutocompleteEntriesWithSubstring:substring];
return YES;
}
- (void)searchAutocompleteEntriesWithSubstring:(NSString *)substring
{
autocompleteMArray = [[NSMutableArray alloc] init];
[autocompleteMArray removeAllObjects];
for(NSString *curString in sCategory) { //**** sCategory is a mutable array generated in another method not shown ****
NSRange substringRange = [curString rangeOfString:substring];
if (substringRange.length > 0) {
[autocompleteMArray addObject:curString];
}
}
NSLog(#"*******The autocompleteMArray : %# ", autocompleteMArray);
[autocompleteTableView reloadData];
}
-(void)cofigureAutoComTableView
{
autocompleteTableView = [[UITableView alloc] initWithFrame:CGRectMake(self.txtActivity.frame.origin.x-10,self.txtActivity.frame.origin.y+32,self.txtActivity.frame.size.width, 120) style:UITableViewStylePlain];
autocompleteTableView.delegate = self;
autocompleteTableView.dataSource = self; //**** Setting this to self, is it correct???
autocompleteTableView.scrollEnabled = YES;
autocompleteTableView.hidden = YES;
[self.view addSubview:autocompleteTableView];
}
- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView {
return 1;
}
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
return autocompleteMArray.count;
}
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
static NSString *cellIdentifier = #"cellIdentifier";
UITableViewCell *cell = [self.autocompleteTableView dequeueReusableCellWithIdentifier:cellIdentifier];
if(cell == nil)
{
cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:cellIdentifier];
}
cell.textLabel.text = [autocompleteMArray objectAtIndex:indexPath.row];
return cell;
}
- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath (NSIndexPath *)indexPath;
{
//**** NOT DETECTING *******
NSLog(#"Selected Cell %#", [autocompleteMArray objectAtIndex:indexPath.row]);
}

Answer 1

If substringRange length is 0 then assign sCategory array to autocompleteMArray and reload the tableview.
- (void)searchAutocompleteEntriesWithSubstring:(NSString *)substring
{
autocompleteMArray = [[NSMutableArray alloc] init];
[autocompleteMArray removeAllObjects];
if ([substring length] == 0)
{
for(NSString *curString in sCategory)
{ //**** sCategory is a mutable array generated in another method not shown ****
NSRange substringRange = [curString rangeOfString:substring];
if (substringRange.length > 0)
{
[autocompleteMArray addObject:curString];
}
}
}
else
{
autocompleteMArray = sCategory;
}
NSLog(#"*******The autocompleteMArray : %# ", autocompleteMArray);
[autocompleteTableView reloadData];
}

Answer 2

- (BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string {
if([[NSString stringWithFormat:#"%#%#",textField.text,string] isEqualToString:#""]) {
autocompleteTableView.hidden = YES;
} else {
autocompleteTableView.hidden = range.location == 0 ? YES : NO;
NSString *substring = [NSString stringWithString:textField.text];
substring = [substring stringByReplacingCharactersInRange:range withString:string];
[self searchAutocompleteEntriesWithSubstring:substring];
}
return YES; }